Ever since I became a runner in high school, I have had an "athletic calf" (as one shoe saleslady told me, while I was shopping for knee-high boots). It can make knee-high boot shopping a little more tedious, since I have to find a pair that has a little piece of stretchy fabric at the top, but otherwise I haven't had a problem with them.
There are times when I get a little bit insecure about my "chubby" calves, but for the most part, I know that they're like that because they're in good shape, not because they're flabby. I like being muscular and able to kick ass, in general. And to me, that makes all the difference.